Many studies including a recent nationwide survey (NCOA, 1975) point to the tendency of old people to express satisfaction with life conditions judged negative by observers. This response tendency may indicate genuine satisfaction, but adaptation, cognitive consistency and self-perception theories all predict it reflects response bias. An explanatory model developed in a study (Campbell et al., 1976) of determinants of satisfaction with life circumstances accounts fairly well for data on persons below the age of 55 but is not explanatory with regard to life quality of those 55 and older. A modification of the Campbell et al. model is being tested, using data from a California sample of people 60 plus in three areas of major concern to the elderly and common to both the NCOA and Campbell et al. studies (health, housing and income). Hypotheses concern effects upon response related to: (1) question and response format, (2) realities of the life domain to which items refer, and (3) individual differences among the respondents in coping resources and coping style. While data collection focuses on older people, use of an extended Campbell et al. model will allow integration of results with those of the earlier study to project an adult life-span explanatory model.